What type of pain is shingle pain?

Shingles Pain: Characteristics and Management

Shingles pain is primarily neuropathic in nature, characterized by burning, tingling, itchy, and tender sensations that can sometimes be sharp. 1

Pain Characteristics of Shingles (Herpes Zoster)

• Post-herpetic neuralgia (PHN) pain occurs at the site of herpes zoster infection and is continuous in nature 1
• The pain is typically described as burning, tingling, itchy, and tender, though it can be sharp at times 1
• Pain severity ranges from moderate to severe and is often aggravated by light touch and eating 1
• Patients commonly experience allodynia (pain from normally non-painful stimuli) and hyperalgesia (increased pain sensitivity) 1
• Burning pain typically precedes the rash by several days and can persist for several months after the rash resolves 2

Pathophysiology of Shingles Pain

• Shingles pain results from reactivation of the varicella-zoster virus that lies dormant in dorsal root ganglia after an initial chickenpox infection 2
• The pain mechanism involves damage to peripheral and central neurons, which may be a byproduct of the immune/inflammatory response accompanying virus reactivation 3
• Hyperexcitability develops in affected nerve pathways, causing spontaneous firing of damaged nerves that manifests as burning pain 4
• Small fiber involvement is particularly associated with the burning sensations experienced in shingles 4

Post-Herpetic Neuralgia (PHN)

• Post-herpetic neuralgia is the most common complication of shingles, occurring in about one in five patients 5
• PHN is defined as pain in a dermatomal distribution that persists for at least 90 days after acute herpes zoster 5
• Patients may experience multiple types of pain including:
  • Constant deep, aching, or burning pain
  • Paroxysmal, lancinating (sharp, stabbing) pain
  • Hyperalgesia
  • Allodynia 6
• PHN significantly decreases quality of life and interferes with activities of daily living 3

Management of Shingles Pain

Acute Phase Treatment

• Antiviral medications (acyclovir, valacyclovir, famciclovir) are most effective when started within 72 hours of rash onset 2
• The addition of oral corticosteroids can provide modest benefits in reducing acute pain and the incidence of postherpetic neuralgia 2

Post-Herpetic Neuralgia Treatment

• First-line medications include:
  • Calcium channel α2-δ ligands (gabapentin and pregabalin) 3
  • Tricyclic antidepressants (amitriptyline, nortriptyline, or desipramine) 3
  • Topical lidocaine patches 3
• Pregabalin is FDA-approved for neuropathic pain that follows healing of shingles 7
• Topical capsaicin may be used for selected patients 2
• For severe pain, opioids or tramadol may be required, though side effect profiles must be considered 6

Special Considerations

• Older adults are at higher risk for developing both herpes zoster and post-herpetic neuralgia 5
• Patients with decreased cell-mediated immunity (e.g., HIV infection, chemotherapy, malignancies, chronic corticosteroid use) are 20-100 times more likely to develop herpes zoster 5
• Ocular involvement in herpes zoster can lead to rare but serious complications and generally merits referral to an ophthalmologist 2
• Prevention through vaccination is recommended for adults 60 years and older, except for certain immunosuppressed patients 5
• Rarely, shingles may present without pain, particularly in elderly patients 8

Treatment Algorithm

1. For acute herpes zoster: Start antiviral therapy within 72 hours of rash onset 2
2. For post-herpetic neuralgia:
   • Begin with either pregabalin/gabapentin, tricyclic antidepressants, or topical lidocaine 3
   • Consider combination therapy with both topical and systemic agents for optimal outcomes 6
   • Adjust medications based on patient response, side effects, and comorbidities 3
   • For refractory pain, consider adding capsaicin, nerve blocks, or opioids 2